The present invention relates to a suction gas valve apparatus of a reciprocating compressor, and in particular to a suction gas valve apparatus of a reciprocating compressor which is capable of promoting an efficiency of a refrigerant by minimizing a heat transmission between a suction gas valve apparatus and the refrigerant by improving respondency of a suction gas valve and simplifying its structure.
In general, a compressor compresses a fluid such as refrigerant gas, etc. A compressor is constructed with a motor part generating a driving force and a compression part compressing a fluid by being transmitted the driving force. A shape of the compression part is various, but in general a piston inserted into a cylinder is transmitted the driving force from the motor part, sucks a fluid, compresses the fluid and discharges it while performing a linear reciprocating motion inside the cylinder.
FIG. 1 is a sectional view illustrating a piston and a suction gas valve apparatus of a compressor installed to the piston in accordance with the prior art. As depicted in FIG. 1, in a suction gas valve apparatus of a compressor in accordance with the prior art, a piston 10 is inserted into a cylinder 1. Herein, the piston 10 inserted into the cylinder 1 is constructed with a cylindrical body unit 11 having a certain diameter and a certain length, a valve mounting portion K formed at a certain end of the cylindrical body unit 11 in order to be mounted with a suction valve body 20 and a hole H having a certain diameter and a certain length and formed at the other end of the cylindrical body unit 11.
In the cylindrical body unit 11, a mounting groove 12 having a certain diameter and a length is formed at an end of the cylindrical body unit 11, and a multistage mounting protrusion portion N is protrusively formed from a bottom surface of the mounting groove 12 in a upward direction. By the mounting groove 12 formed at the end of the cylindrical body unit 11, a ring-shaped rim portion 13 having a certain length and a width in a circumference direction of the piston 10 is formed, and the inner end of the rim portion 13 forms a first valve seat 14 declined to a center of the piston 10. A plurality of suction holes 15 connected to the mounting groove 12 are formed at the rim portion 13.
And, the mounting protrusion portion N includes a fist circular protrusion 16 upwardly extended-formed from the bottom surface of the mounting groove 12 so as to be smaller than an outer diameter of the mounting groove 12 and have an outer diameter same as an inner diameter of the mounting groove 12, and a second circular protrusion 17 formed at the upper surface of the first circular protrusion 16 so as to have a smaller diameter than the outer diameter of the first circular protrusion 16 and have a certain height.
And, a through hole 18 is formed at the center portion of the first and the second circular protrusions 16, 17 so as to connect to the hole H formed at the opposite side of the mounting protrusion portion N. Herein, the height of the first and the second circular protrusions 16, 17 is lower than the height of the rim portion 13. And, the rim portion 13 of the first circular protrusion 16 is projected so as to have a sloping side declined to the center of the piston 10 and forms a second valve seat 19 with the upper surface of the first circular protrusion 16.
And, a suction valve body 20 installed inside the valve mounting portion K of the piston 10 has a certain height and a conic shape with a plane upper surface. The outer circumference of the suction valve body 20 is formed so as to be stepped, the upper outer circumference having a bigger outer diameter consists a first contact surface 21, the lower outer circumference having a smaller outer diameter consists a second contact surface 22. A plane bottom surface having a small area consists a third contact surface 23.
And, a through hole 24 is formed at the center portion of the suction valve body 20, a first insertion groove 25 is formed at the center portion of the third contact surface 23 so as to have an inner diameter and a height corresponded to the outer diameter and the height of the second circular protrusion 17 of the valve mounting portion K of the piston 10, and a second insertion groove 26 is formed at the center portion of the bottom surface of the suction valve body 20 so as to have a certain inner diameter and a depth. The inner diameter of the first insertion groove 25 is larger than the inner diameter of the second insertion groove 26, the center lines of the first and the second insertion grooves 25, 26 are placed at the line same as the center line of the through hole 24.
Hereinafter, installing the suction valve body 20 to the piston 10 will now be described in detail.
First, a first insertion groove 25 of the suction valve body 20 is inserted into the second circular protrusion 17 of the valve mounting portion K. Herein, the part of the third contact surface 23 and the second contact surface 22 of the suction valve body 20 is contacted to the second valve seat 19, and the first contact surface 21 is contacted to the first valve seat 14. In addition, the through hole 24 of the suction valve body 20 is combined to the through hole 18 of the piston 10 by corresponding their center lines.
And, a combining guide rod 30 having a certain length and head units 31, 31xe2x80x2 at both ends is combined inside the through hole 18 of the suction valve body 20 and the through hole 18 of the piston 10. The head unit 31 combined to the end of the combining guide rod 30 is placed inside the second insertion groove 26 of the suction valve body 20, the height of the head unit 31 is lower than the height of the second insertion groove 26 and the outer diameter of the head unit 31 is smaller than the inner diameter of the second insertion groove 26. In addition, the head unit 31xe2x80x2 combined to the other end of the combining guide rod 30 is placed inside the hole H formed at the lower end of the cylindrical body unit 11. Accordingly, the suction valve body 20 can move up and down although the combining guide rod 30 is combined to.
Hereinafter, the operation of the suction gas valve apparatus of the compressor in accordance with the prior art will now be described.
The suction valve body 20 is open and shut by a pressure difference between up and down of the suction valve body 20 and an inertia force due to a motion of the piston 10. First, as depicted in FIG. 2, when the piston 10 transmitted the driving force moves from a upper dead center to a bottom dead center, namely, in an xe2x80x9caxe2x80x9d direction, gas flows into a suction hole 15 by a suction force, and the gas is sucked into the cylinder 1 through the first contact surface 21 of the mounting groove 12 and the first valve seat 14 of the suction valve body 20 while the suction valve body 20 moves in xe2x80x9caxe2x80x9d direction opposite to the piston moving direction according to the combining guide rod 30.
And, when the piston 10 moves from a lower dead center to a upper dead center, namely, in a xe2x80x9cbxe2x80x9d direction, suctioning the gas into the suction hole 15 is stopped, the first contact surface 21 of the suction valve body is mounted on the first valve seat 14, the lower portion of the second contact surface 22 and the third contact surface 23 are contacted to the second valve seat 19 and are sealed while the suction valve body 20 moves to a lower portion according to the combining guide rod 30 by a pressure, and the gas flowed into the cylinder 1 is compressed
By performing the above-mentioned process, the gas flows into the cylinder 1.
However, in the above-mentioned structure in accordance with the prior art, because the suction valve body 20 is open and shut only by the pressure difference between up and down of the suction valve body 20 and the inertia force by the motion of the piston 10, the respondency of the suction valve body 20 is not good.
In addition, in the above-mentioned structure in accordance with the prior art, because the combining guide rod 30 penetrates the suction valve body 20 and the piston 10, in order to prevent leakage of refrigerant due to the penetration, a sealing member is inserted between the second valve seat 19 and the second and the third contact surfaces 22, 23 of the suction valve body 20, and between the head unit 31 of the combining guide rod 30 and the piston 10, etc., accordingly its structure is complicated and its processing is difficult.
And, because the combining guide rod 30 is inserted into the second insertion groove 26 of the suction valve body 20, a dead volume always exists, accordingly a re-expansion loss occurs.
It is an object of the present invention to provide a suction gas valve apparatus of a reciprocating compressor which is capable of improving an efficiency of a refrigerant by simplifying its structure.
It is another object of the present invention to provide a suction gas valve apparatus of a reciprocating compressor which is capable of improving respondency of a suction valve body and minimizing a dead volume.
In order to achieve the above-mentioned objects, there is provided a suction gas valve apparatus of a reciprocating compressor in accordance with the present invention including a piston having a gas passage at which gas flows inside its cylindrical body unit, a valve seat formed at an end of the piston body unit to open the gas passage and a step face formed so as to have a thickness inward from the valve seat and have a plurality of gas through holes and a mounting through hole, and a valve cone having a detachable coupling portion formed extendedly from a cone portion corresponded to the valve seat of the piston and inserted into the mounting through hole of the step face of the piston so as to be movable.